Non-scalable to scalable video converter

ABSTRACT

Systems and methods are for implementing a NSV2SV converter that converts a non-scalable video signal to a scalable video signal. In an implementation, a non-scalable video signal encoded in H.264/AVC standard is decoded and segmented into spatial data and motion data. The spatial data is resized into a desired resolution by down-sampling the spatial data. The motion data is also resized in every layer, except in the top layer, of a scalable video coding (SVC) encoder by using an appropriate measure. Further, the motion data is refined based on the resized spatial data in every layer of the SVC encoder. The refined motion data and the down-sampled spatial data are then transformed and entropy encoded in the SVC standard in every layer. The SVC encoded output from every layer is multiplexed to produce a scalable video signal.

FIELD OF THE INVENTION

The present invention relates to the field of video, and moreparticularly to video encoders and related methods.

BACKGROUND OF THE INVENTION

Digital video services have enabled improved quality video signaltransmission, resulting in an immaculate video display at the consumerend. Among various video coding standards available, Moving PictureExperts Group-2 (MPEG-2) is very popular, as it can be applied todiversified bit rates and sample rates. Additionally, the MPEG-2 videocoding standard provides mature and powerful video coding methods andsupports scalability.

In order to cater to newer transmission media such as Cable Modem, xDSL,or UMTS, H.264/Advanced Video Coding (AVC) standard is gainingpopularity as the basis of digital video transmission. This is becauseof its higher coding efficiency, lower bit rate, efficient bandwidthutilization, error resilience, low processing delay, support forscalability, and capability to produce high quality video. Moreover,H.264/AVC enables transmission of more video channels or higher qualityvideo representations within the existing digital transmissioncapacities.

With the advent of a variety of end user devices and time varyingnetworks, video adaptation on the various end user devices forappropriate video presentation has become very critical. For example, inbroadcast, simulcast, or multicast transmissions, the same signal may bereceived by various end user devices, such as televisions, cell phones,computing devices, etc. The end user devices can have differentcharacteristics in screen sizes, life span of power supplies, memorycapabilities, CPU's, etc. This makes the task of video adaptability onthe targeted end devices very challenging even while using the videocoding standards such as MPEG-2, H.264/AVC, etc.

As a result, scalable video coding schemes are emerging that make itpossible to adapt the bit rate and quality of a transmitted stream tothe network bandwidth on which the stream is transmitted. The ScalableVideo Coding or SVC standard has been developed as an extension to theH.264/AVC standard. Among several scalabilities, spatial scalability,i.e. video adaptability through different spatial resolutions, is one ofthe key features generally required in scalable video streaming overheterogeneous devices such as mobile phones, televisions, personaldigital assistants (PDAs), laptops, and so on. However, appropriatetechniques for achieving spatial scalability and producing a scalablevideo signal subsuming multiple distinct resolutions from a non-scalablevideo signal are currently unavailable.

SUMMARY OF THE INVENTION

This summary is provided to introduce concepts related to a non-scalableto scalable video (NSV2SV) converter, which is further described belowin the detailed description. This summary is not intended to identifyessential features of the claimed subject matter, nor is it intended foruse in determining the scope of the claimed subject matter.

In one embodiment, a system including a broadcasting system, a NSV2SVconverter, and a receiving device can be used. The NSV2SV converterproduces an output video signal in a scalable format, hereinafterreferred to as scalable-video signal, from a received input video signalin a non-scalable format, hereinafter referred to as non-scalable videosignal. The scalable video signal may be in the form of a multi-layerbit stream in which each layer corresponds to a different resolution.The non-scalable input video signal, typically, has a single bit-streamcoded in a standard that supports scalability, such as H.264/AVCstandard, MPEG-2.

In one implementation, the broadcasting system can transmit thenon-scalable video signal to an intermediate device. The intermediatedevice includes the NSV2SV converter, which is configured to convert thenon-scalable video signal into the scalable video signal conforming to ascalable video standard, for example, the Scalable Video Coding (SVC)standard. The receiving device receives the scalable output video signalfrom the intermediate device. Further, the receiving device can extractand use the layers that correspond to a resolution supported by thereceiving device, from the multiple layered bit stream included in thescalable output video signal. In another implementation, the receivingdevice may receive only those layers that correspond to the supportedresolution, from the intermediate device.

In particular, the NSV2SV converter includes a decoder that decodes thenon-scalable input video signal. Spatial data and motion data aresegmented from the decoded video signal. A spatial down-converter moduledown-samples and resizes the spatial data to the different resolutions.The resized spatial data and the segmented motion data are thenprocessed by an encoder. To generate the multi-layer bit stream, theencoder includes multiple encoding layers, each of which generates abit-stream layer corresponding to a distinct resolution.

In the encoding layers, the motion data is resized and refined tocorrespond to the different resolutions. For this, the encoding layersinclude a motion/texture information adaptation module (M/TIAM), alsoreferred to as an adaptation module, and a motion refinement module(MRM). The adaptation module adapts the motion data from the decodedsignal to the corresponding resolution of that encoding layer. For this,the adaptation module reuses the original motion data included in thenon-scalable input video signal and produces adapted motion data. Themotion refinement module (MRM) refines the adapted motion data based onthe down-sampled spatial data for improving the resolution quality inthat encoding layer. In one embodiment, in the top most encoding layer,the MRM, refines the segmented motion data based on the down-sampledspatial data. In such an embodiment, the top most encoding layer may notinclude the adaptation module.

Further, in the encoding layers, the output of the MRM, including therefined spatial and motion data, is transformed and encoded in atransform and entropy encoding module (TEC). In one implementation, therefined spatial and motion data is transformed into discrete cosinetransform (DCT) coefficient values. Subsequently, the DOT coefficientvalues are entropy encoded. Thus multiple encoded bit stream layerscorresponding to different resolutions are generated by the encodinglayers. Further, the output signals of the TEC modules from thedifferent encoding layers are multiplexed to produce a scalable videosignal having a multi-layer bit stream subsuming a distinct resolutionin each layer.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Thesame numbers are used throughout the drawings to reference like featuresand components.

FIG. 1 illustrates an exemplary system implementing a Non-Scalable toScalable Video (NSV2SV) converter in accordance with the presentinvention.

FIG. 2 illustrates another exemplary system implementing a NSV2SVconverter in accordance with the present invention.

FIG. 3 illustrates an exemplary NSV2SV converter in accordance with thepresent invention.

FIG. 4 illustrates an exemplary block diagram of a NSV2SV converter inaccordance with the present invention.

FIGS. 5 a and 5 b illustrate an exemplary method for implementing aNSV2SV converter in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The disclosed subject matter relates to a non-scalable to a scalablevideo (NSV2SV) converter. More particularly, the subject matter relatesto techniques for trans-coding non-scalable video content coded in videocompression standards which support scalability, such as MPEG-2,H.264/AVC, and so on, into scalable video content in scalable videocompression standards such as SVC. The disclosed techniques are based onfine-to-coarse-to-fine code conversion methods.

In an implementation, a system including a broadcasting system, a NSV2SVconverter, and a receiving device can be used for generating and using ascalable-video signal from a broadcasted non-scalable video signal. Thenon-scalable video signal, typically, is a single bit-stream coded in astandard that supports scalability, such as 8.264/AVC standard, MPEG-2and so on. The scalable video signal is in the form of a multi-layer bitstream in which each layer corresponds to a different resolution. In oneimplementation, the broadcasting system can transmit the non-scalablevideo signal to an intermediate device. The intermediate device includesthe NSV2SV converter, which is configured to convert the non-scalableinput video signal into the scalable output video signal. The receivingdevice receives the scalable output video signal from the intermediatedevice.

The NSV2SV converter can be implemented in a variety of electronic orcommunication devices in which a non-scalable video signal possessing ahigh resolution can be adapted and transmitted for display according tothe display capabilities of the targeted end devices. Devices that canimplement the disclosed NSV2SV converter include, but are not limitedto, set-top boxes, base transceiver system (BTS), computing devices,televisions, mobile phones, laptops, personal digital assistants (PDAs),and so on, which can be employed in a variety of applications such asstreaming, conferencing, surveillance, etc.

The NSV2SV converter can be thus advantageously used for transmittingscalable video signals to a variety of end user devices, in a resolutionthat is supported by the end user devices. The NSV2SV converter alsoenables efficient decoding of the video content received over diversenetworks as it provides an option of decoding only a part of a theplurality of signals of different resolutions included in the scalablevideo signal.

Additionally, as compared to alternative approaches of recreating themotion information from the non-scalable input video signal forproducing the scalable output video signal, the NSV2SV converter reusesthe original motion information included in the input video signal,thereby reducing the complexity and computational load on an encoder andmaintaining higher coding efficiency. Further, the NSV2SV converter alsoprovides for improved efficiency use of network bandwidth and systemmemory as the non-scalable video signal can be converted once into thescalable video signal and saved in memory. The scalable video signal canthen be transmitted multiple times to different end user devices as perthe resolution capabilities of the end user devices.

Exemplary Systems

FIG. 1 illustrates an exemplary system 100 implementing a non-scalableto scalable video (NSV2SV) converter. The system 100 includes asatellite 102 and broadcasting station servers 104 communicating via anetwork 106. The broadcasting station servers 104 may be used forbroadcast, simulcast, or multicast transmissions. The broadcastingstation servers 104 may be implemented as any of a variety ofconventional computing devices including, for example, a general purposecomputing device, multiple networked servers (arranged in clusters or asa server farm), a mainframe, and so forth.

The network 106 may be a wireless or a wired network, or a combinationthereof. The network 106 can be a collection of individual networks,interconnected with each other and functioning as a single large network(e.g., the Internet or an intranet). Examples of network 106 include,but are not limited to, Local Area Network (LAN), Wide Area Network(WAN), and so on.

The system further includes an intermediate device 108 communicatingwith the broadcasting station servers 104 via the network 106. Theintermediate device 108 is connected to one or more end devices 112-1,112-2, 112-3, . . . 112-N (hereinafter collectively referred to as enddevices 112). The end devices 112 may be implemented as any of a varietyof conventional computing devices, including, for example, a server, adesktop PC, a notebook or a portable computer, a workstation, a personaldigital assistant (PDA), a mainframe computer, a mobile computingdevice, an Internet appliance, and so on.

In one implementation, the broadcasting station servers 104 can beconfigured to transmit video signals encoded in any of a variety ofvideo coding standards such as H.264/AVC, H.263, MPEG-2, and so on. Thetransmitted video signal can be a non-scalable video signal subsuming asingle layer bit stream of a certain input resolution. The non-scalablevideo signal can be transmitted from the satellite 102 either directlyor via the broadcasting station servers 104 to an intermediate device108 such as a set-top box, a base station transceiver system (BTS), andso on.

The intermediate device 108 includes a non-scalable video to scalablevideo (NSV2SV) converter 110 for converting the non-scalable videosignal into a scalable video signal. The output scalable video signalcan be a signal that subsumes a multi-layer bit stream corresponding toa distinct resolution in each layer. The scalable video signal is thentransmitted to one or more of the end devices 112 for furtherprocessing.

In one implementation, the intermediate device 108 can be equipped withan extractor that receives information regarding the resolutionsupported by a target end device, such as 112-1. The extractor thenextracts the layers corresponding to the supported resolution from themulti-layer bit stream and transmits the extracted layers to the targetend device 112-1. The extracted layers are then decoded and rendered atthe target end device 112-1. In another implementation, each of the enddevices 112 includes an extractor that extracts the layers correspondingto the supported resolutions from the multi-layer bit stream. Theextracted layers are then decoded and rendered at the end devices 112.

FIG. 2 illustrates another exemplary system 200 implementing anon-scalable to scalable video (NSV2SV) converter. The system 200includes the satellite 102 and the broadcasting station servers 104communicating via the network 106.

The system 200 further includes end devices 202-1, 202-2, 202-3, and202-4 (collectively, devices 202) communicating with the broadcastingstation servers 104 via the network 106. The end devices 202 may beimplemented as any of a variety of conventional computing devices,including, for example, a server, a desktop PC, a notebook or a portablecomputer, a workstation, a personal digital assistant (PDA), a mainframecomputer, a mobile computing device, an Internet appliance, and so on.

In one implementation, the broadcasting station servers 104 can beconfigured to transmit video signals encoded in any of a variety ofvideo coding standards such as H.264/AVC, H.263, MPEG-2, and so on. Thetransmitted video signal can be a non-scalable video signal subsuming asingle layer bit stream of a certain input resolution. The non-scalablevideo signal can be transmitted from the satellite 102 either directlyor via the broadcasting station servers 104 to the end devices 202.

In another implementation, the Broadcasting servers can be integratedwith the NSV2SV converter directly. The broadcaster can then, convert anon-scalable video signal subsuming a single layer bit stream of acertain input resolution to a scalable video signal that subsumes amulti-layer bit stream having distinct resolution in each layer. Thescalable video can be transmitted to the end devices, from thebroadcasting stations either directly to or via the satellite, throughthe network devices consisting of an bit stream extractor which wouldtransmit the video signal at the resolution for the end device.

In one implementation, each of the end devices 202 can be equipped withan extractor that receives information regarding the resolutionsupported by the respective end device. The extractor then extracts thelayers corresponding to the supported resolution from the multi-layerbit stream. The extracted layers are then decoded and rendered at therespective end device.

FIG. 3 illustrates an exemplary NSV2SV converter 110. The NSV2SVconverter 110 includes one or more processors 302, one or moreinterfaces 304, a decoder 306, a system memory 308 that includes aspatial data module 310 and a motion data module 312, a spatialdown-converter module 314, an encoder 316 and a multiplexer 318. Theprocessor(s) 302 may include, for example, microprocessors,microcomputers, microcontrollers, digital signal processors, centralprocessing units, state machines, logic circuitries, and/or any devicesthat manipulate signals based on operational instructions. Among othercapabilities, the processor(s) 302 are configured to fetch and executecomputer-readable instructions stored in the memory 308.

The interface(s) 304 can include a variety of software interfaces, forexample, application programming interface, hardware interfaces, forexample cable connectors, or both. The interface(s) 304 facilitatereceiving of the input non-scalable video signal and reliabletransmission of the output scalable video signal

A decoder 306 decodes a received input signal to produce a decodedsignal. The received input signal can be a non-scalable video signalcoded in any video coding standard, such as H.264/AVC, MPEG-2, and soon, that supports scalability. The decoded signal can be adapted in anyintermediate format such as Common Intermediate Format (CIF), QuarterCommon Intermediate Format (QCIF), and so on. The processors(s) 302segment the decoded signal into spatial data and motion data, which arestored in the system memory 308.

The system memory 308 can include any computer-readable medium known inthe art, including, for example, volatile memory (e.g., RAM) and/ornon-volatile memory (e.g., flash, etc.). In one implementation, thesystem memory 308 includes a spatial data module 310 and a motion datamodule 312. The spatial data module 310 stores the decoded spatial dataas pixel data information. The pixel data can be associated withattributes such as, for example, picture data, picture width, pictureheight, and so on, in a picture frame of the video sequence. The motiondata module 312 stores the segmented motion data describing motionattributes, such as, for example, frame rate, picture type, end ofstream flag, sequence frame number, motion vectors, Intra predictionmode, the location of different components in a picture frame such aspixels, blocks, macroblocks (MBs) and so on, and other relatedattributes such as MB modes, MB type, MB motion type, etc.

In operation, on receipt of a non-scalable input video signal, thedecoder 306 decodes the input signal, which is then segmented into thespatial data and the motion data. The spatial data and the motion dataare stored in the spatial data module 310 and the motion data module 312respectively.

The spatial down-converter module 314 receives the spatial data from thespatial data module 310 and down-samples the spatial data for resizingthe spatial data to conform to the different resolutions to be providedin the scalable output video signal. The down-sampling operation can beperformed using a variety of techniques well known in the art. Forexample, the spatial data can be down-sampled by using various imagecompression filters such as polyphase filters, wavelet filters, and soon. The down-sampled spatial data and the segmented motion data are thenfed to the encoder 316 for further processing.

The encoder 316 processes the decoded signal including the resizedspatial data and the segmented motion data to produce a scalable videosignal conforming to a video coding standard that is adaptable to theend devices 112, 202. Towards this end, the encoder 316 includes one ormore encoding layers for encoding the previously decoded signalsuccessively into multiple encoded signals such that each encoded signalcorresponds to a distinct resolution.

The multiple encoded signals include an encoded base signal thatincludes the video signal in the basic or most coarse resolution form.The successive encoded signals include information for enhancing or finetuning the coarse resolution progressively. Thus each encoded signal,when used in combination with encoded signals from previous encodinglayers, provides a video signal of the corresponding distinctresolution.

The encoded signals from the multiple encoding layers of the encoder 316are fed to the multiplexer 318. The multiplexer 318 multiplexes theencoded signals into a single encoded output video signal. The encodedoutput video signal exhibits spatial scalability due to the presence ofmultiple layers corresponding to distinct resolutions.

FIG. 4 illustrates an exemplary block diagram of a NSV2SV converter 110.The order in which the blocks of the system are described is notintended to be construed as a limitation, and any number of thedescribed system blocks can be combined in any order to implement thesystem, or an alternate system. Furthermore, the system can beimplemented in any suitable hardware, software, firmware, or acombination thereof, without departing from the scope of the system.

The NSV2SV converter 110 is capable of converting a non-scalable inputvideo signal 402, hereinafter referred to as input signal 402, to ascalable output video signal 404, hereinafter referred to as outputsignal 404. In an implementation, the input signal 402 can be coded inH.264/AVC standard. In such a case, the input signal 402 is a singlelayer bit stream of a certain input resolution. The input signal 402 canbe trans-coded into a scalable video coding (SVC) standard output signal404 by the NSV2SV converter 110. In such a case, the output signal 404subsumes a multi-layer bit stream corresponding to a distinct resolutionin each layer and conforms to the SVC standard for video coding.

The scalable video coding (SVC) standard for video coding can beadvantageously used for coding the output signal as it provides bitstream scalability for video signals. The SVC standard enables encodingof a high-quality input video signal into multiple sub-streamsrepresenting a lower spatial or temporal resolution or a lower qualityvideo signal (each separately or in combination) as compared to theoriginal bit stream. SVC also supports functionalities such as bit rate,format, and power adaptation. SVC further provides graceful degradationin lossy transmission environments as well as lossless rewriting ofquality-scalable SVC bit streams to single-layer H.264/AVC bit streams.Additionally, SVC has achieved significant improvements in codingefficiency with an increased degree of supported scalability relative tothe scalable profiles of prior video coding standards.

In one implementation, the NSV2SV converter 110 transforms the inputsignal 402 into the spatially scalable output signal 404 by convertingthe input signal 402 into the SVC standard format. For the abovementioned purpose, in an embodiment, the NSV2SV converter 110 includesthe decoder 306, a segmentation section 406, the encoder 316 and themultiplexer 318.

In an implementation, the input signal 402 including a single layer bitstream, which is coded in, for example, H.264/AVC standard, is receivedby the decoder 306. At block 408, variable-length decoding (VLD) isperformed on the received input signal 402 using techniques well knownin the art. The variable-bit length decoding provides pixel and motioninformation based on the length of each Huffman code used to encode theinput signal 402. The variable length decoded signal is then sent toblock 410 for further processing for retrieval of spatial data and tothe segmentation section 406 for storing and re-using motion data.

At block 410, the decoded signal is processed by application of inversequantization (IQ) to determine the class and quantization number of thequantized discrete cosine transform (DCT) coefficient values included inthe decoded signal. The magnitude of DOT coefficient values representspatial frequencies corresponding to the average pixel brightness in theimages of the input signal 402. The reciprocated quantized DCTcoefficient values are then inversed at an inverse DCT (IDCT) block 412to produce the Pixel values. The output of the MOT block 412 is capableof being used for reconstructing a video sequence from the DCTcoefficients values.

Subsequently, the output of IDCT stage is added to the output of amotion compensation block 414 in an adder 416 to produce a decoded videosequence signal. Motion compensation is a technique of describing apicture in terms of transformation of a reference picture, located in apicture buffer 418, to the current picture. The output of the motioncompensation block 414 provides differences between the referencepicture and the current picture and is used for predicting pictureframes for display. A variety of motion compensation techniques such asblock motion compensation, overlapped motion compensation, variableblock-size motion compensation, and so on can be employed to obtain theoutput and generate the decoded signal.

The decoded signal is then transmitted to the segmentation section 406.The segmentation section 406 includes a spatial data module 310, amotion data module 312, and a spatial down-converter module 314. In thesegmentation section 406, the decoded signal is segmented to providespatial data and motion data, which are stored in the spatial datamodule 310 and the motion data module 312 respectively. The spatial datamodule 310 stores the decoded spatial data as pixel data information.The pixel data can be associated with attributes such as, for example,picture data, picture width, picture height, and so on, in a pictureframe of the video sequence. The motion data describes the location ofdifferent components such as pixels, blocks, macroblocks (MBs) and soon, of a picture frame and other related attributes such as MB modes, MBmotion type and so on.

Subsequently, the spatial data is fed to the spatial down-convertermodule 314. The spatial down-converter module 314 down-samples thespatial data using various image compression filters such as polyphasefilters, wavelet filters, and so on. Down-sampling of the spatial datareduces the data rate and/or the size of data. The reduction in size ofspatial data is achieved based on the desired resolutions such as CommonIntermediate Format (CIF) resolution, Quarter CIF (QCIF) resolution, andso on, in the scalable video output signal. The resized spatial data andthe segmented motion data are then forwarded to the encoder 316.

The encoder 316 subsumes a multitude of encoding layers with each layercorresponding to a distinct resolution as explained earlier withreference to FIG. 3. The following description of the working of theencoder 316 has been provided with reference to 3 encoding layers.However, it will be understood that the encoder 316 can include anynumber of encoding layers and will work in a similar manner as thatdescribed herein.

In one implementation, when the encoder 316 includes three encodinglayers, the encoder 316 includes two motion/texture info adaptationmodules (M/TIAMs) 420-1 and 420-2, and three motion refinement modules(MRMs) 422-1, 422-2, and 422-3. The encoder 316 also includes threetransform and entropy encoding modules (TECMs) 424-1, 424-2, and 424-3,and two inter-layer prediction modules (ILPMs) 426-1 and 426-2. Thesemodules can be distributed over the three encoding layers, namely a baselayer 428, an enhancement layer I 430, and an enhancement layer II 432.

In one embodiment, the base layer 428 includes the M/TIAM 420-1, the MRM422-1, and the TECM 424-1. The enhancement layer I 430 includes M/TIAM420-2, MRM 422-2, TECM 424-2, and ILPM 426-1. The enhancement layer II432 includes MRM 422-3, TECM 424-3, and ILPM 426-2. The motion data andthe down-sampled spatial data received from the segmentation section 406are fed to all the layers of the encoder 316.

Base Layer

In an implementation, the base layer 428 receives the spatial data fromthe spatial down-converter module, which has been resized to the desiredQCIF resolution, for example, 176×144 by the spatial down-convertermodule 314. The base layer also receives the segmented motion data forcalculating motion information at the M/TIAM 420-1. The motion data,which includes original motion information from the H.264/AVC codedinput video signal, is adapted so as to produce a resultant QCIF output.The M/TIAM 420-1 calculates the motion information by reusing theoriginal motion information subsumed in the original H.264/AVC codedvideo signal. As the original motion information is re-used and adaptedto generate the motion information, the computational complexityinvolved is reduced by a large extent as compared to generating themotion information from a completely decoded signal. The calculated andadapted motion information is then used for motion estimation.

The technique of motion estimation helps in finding the best matchbetween the pixels in a current video frame, hereinafter referred to ascurrent frame, and the pixels in a reference video frame, hereinafterreferred to as reference frame. The current frame corresponds to thecomplete picture that is in the process of construction, for a videosequence. The reference frame corresponds to an already constructedcomplete picture in a video sequence used to describe the current frame.

In the technique of motion estimation, a search area within thereference frame is traversed to find a best match for the component inthe current frame. For this, the size of search area and the evaluationmetrics used for determining the best match are the most crucialfactors. The size of the search area corresponds to the appliedcomputational load and the evaluation metrics corresponds to the degreeof coding efficiency. Different types of motion estimation techniquessuch as block matching, pixel recursive technique, and so on are used.The motion estimation techniques use a variety of evaluation metricssuch as Sum of Absolute Differences (SAD), Mean Absolute Differences(MAD), Mean Square Error (MSE), etc.

In an implementation, a search is performed for a macroblock in thereference frame corresponding to a macroblock in the current frame. Thebest match is found by comparing the macroblock in the current framewith the macroblocks in the search area in the reference frame. In oneimplementation, the macroblocks are compared by using difference in thecorresponding pixel values. This provides difference values called asSAD values. The minimum of the SAD values corresponds to the closestlinked pixel value in the reference frame for the current frame. Inother words, a variation in the SAD value can be referred to as the costassociated with the MB. The MB in the reference frame having the minimumcost corresponds to the best match or the best MB available for codingthe MB in the current frame. After finding the best match, thedifference values between the corresponding pixels are coded togetherwith the difference between the corresponding pixel locations. Thelocation of a pixel can be defined by a motion vector.

For the purpose of understanding, consider a block made up of 8×8pixels. Four blocks can be combined together to form a single macroblockof 16×16 pixels i.e.One Macroblock=Four Blocks  (1)16×16 pixels=4×(8×8) pixels  (2)

In an implementation, for producing the QCIF output, macroblock (MB)modes and motion vectors (MVs) are the prime attributes that need to becalculated. An MB mode refers to the degree of partition in the MB. Forexample, inter-mode 1 refers to a MB having one partition of 16×16pixels, inter-mode 2 refers to a MB having two partitions of 16×8pixels, inter-mode 3 refers to a MB having two partitions of 8×16pixels, and so on. Also, the macroblock can be coded using an inter modeor an intra mode. The motion vector refers to a two-dimension vectorused for inter prediction that provides an offset from the coordinatesin the current frame to the coordinates in a reference frame.

Conversion of Input Motion Data to 4QCIF

The MB modes and the MVs from the motion data module 312 togetherconstitute the input motion data (D1), which is adapted to four timesthe intended QCIF resolution (4QCIF). The QCIF resolution corresponds toa resolution of 176×144. This is performed so that, in the next step, adirect mapping can take place for the intended QCIF resolution. This canbe understood by referring to aforesaid equations (1) and (2) and toequations discussed below:16×16 pixels to be reduced to 8×8 pixels  (3)Therefore, 4×(16×16) pixels to be reduced to 4. (8×8) pixels  (4)Or, 4 Macroblocks to be reduced to 1 Macroblock  (5)

The above equations show that the width and height ratio is exactly twobetween 4QCIF and QCIF. Also, since while mapping from D1 to 4QCIF thewidth and height ratios may not be exactly two, the principle ofdominant MB mode can be used to map the MBs from D1 to 4QCIF. Further,based on the MB modes of the candidate MBs in D1, a single MB mode iscalculated for the corresponding MB in 4QCIF. The candidate MBs arethose MBs, which qualify for being mapped based on the width and heightratios, and overlap area.

The MB mode can be calculated by using either forward prediction methodor intra prediction method known in the art. Further, if any of thecandidate MB mode in D1 is intra mode, then the resultant MB mode in4QCIF is calculated as intra mode, irrespective of the dominant MB mode.Further, based on the MVs of all the candidate MBs in D1, the single MVfor 4QCIF can be derived using a variety of techniques already known inthe art. In one implementation, a single MV for 4QCIF can be computed bycalculating the median of the candidate MVs in D1.

Conversion of 4QCIF to QCIF

The MB modes and MVs from 4QCIF are mapped to the intended QCIFresolution, based on the principle of dominant mode. Depending upon theMB modes of a set of four candidate MBs in the 4QCIF resolution, asingle MB mode is derived for the resultant QCIF MB. If any of thecandidate MB modes is intra mode then the resultant MB is also codedusing the intra mode, irrespective of the dominant MB mode among thefour candidate MBs. Also, each MB in 4QCIF is checked by the encoder 316for if it can be skipped. The MB can be skipped if the corresponding MVis zero or very close to zero. This situation can arise when the closetmatching region is at the same or almost at the same location in thereference frame and the energy of a residual MB is low. The residual MBis formed by subtracting the reference MB (without motion compensation)from the current MB. The energy of the residual MB is approximated bySAD values. Therefore, if the cost of coding the MB as skip is lesserthan that decided by the M/TIAM 420-1, then skip mode can be followed.This corresponds to the act of dealing away from the task of coding acurrent macroblock, thus reducing the computational load.

Subsequently, in an implementation, all MBs in the QCIF resolution areset in 8×8 coding mode by using forward prediction method. The 8×8coding mode corresponds to four 8×8 block partitions for each MB.However, if the MBs in the QCIF resolution are intra coded, then theQCIF MBs are not set in 8×8 coding mode. An MV of each 8×8 block of eachMB in the QCIF resolution is set equal to an MV of the corresponding MBin the 4QCIF resolution by scaling it accordingly. The calculated motioninformation including MBs and MVs for the intended QCIF resolution andother related information thereto, is then sent to MRM 422-1 for furtherrefinement of the QCIF resolution.

The MRM 422-1 receives the motion information from the M/TIAM 420-1 andthe resized spatial data from the spatial down-converter module 314. Inthe MRM 422-1, all the calculated MVs of the intended QCIF resolutionfrom M/TIAM 420-1 undergo a refinement process based on the receivedresized spatial data. For the purpose, slight approximations are furtheradded to the motion information, such as the calculated MVs, for findingthe best possible mode for the MB located in the current frame. This isperformed so that the MB located in the current frame is closest to themode of the MB located in the reference frame. The approximations arefound out by using various techniques already known in the art. Theprocess of refinement is carried out at the most granular levelcorresponding to the refinement of motion information at quarter of apixel (QPel) level. The refined motion data and spatial data (RMS) arethen forwarded to TECM 424-1.

In TECM 424-1, in an implementation, RMS subsumed in each block of theQCIF macroblock, which forms the QCIF resolution, is transformed intolow frequency DCT coefficient values using a variety of transformationtechniques already known in the art. RMS is then entropy coded using anumber of entropy coding techniques such as context-based adaptivevariable-length coding (CAVLC), context-based adaptive binary arithmeticcoding (CABAC), and so on. Therefore, a desired encoded QCIF resolutionoutput is received as the output of TEC 424-1, which is sent to amultiplexer 318.

Enhancement Layer

For obtaining an output of another resolution, for example, CIFresolution, as part of the final scalable video signal, the enhancementlayer I 430 is used. In an implementation, the spatial data can beresited to the desired CIF resolution, i.e., 352×288 by the spatialdown-converter module 314 before feeding it to the enhancement layer I430. On the other hand, the motion information from the decoded signal,which includes the original motion information subsumed in the H.264/AVCcoded input video signal, is adapted so as to produce a resultant CIFoutput. Correspondingly, the motion information for the resultant CIFoutput is calculated by reusing the original motion information subsumedin the original H.264/AVC coded video signal. The calculation of motioninformation is performed for motion estimation as described below.

The enhancement layer 1438 includes ILPM 426-1, M/TIAM 420-2, MRM 422-2,and TECM 424-2. The ILPM 426-1 provides an exploitation of thestatistical dependencies between different layers for improving thecoding efficiency of the enhancement layer. The improvement in codingefficiency can be referred to in terms of a reduction in bit rate. TheILPM 426-1 uses various inter-layer prediction methods employing thereconstructed samples of QCIF MB from the base layer 428 to produce aninter-layer prediction signal. The inter-layer prediction signal can beformed by using different methods, such as motion compensated predictioninside the enhancement layer, by up-sampling the reconstructed baselayer signal, and so on. These methods are dependent on variousparameters, for example, prediction of MB modes and associated motionvectors. Correspondingly, the encoder 316 checks for each MB at D1resolution for it can be inter-layer predicted from the base layer 428.Therefore, the encoder 316 checks for intra, motion and residualinter-layer predictions while coding each MB.

The inter-layer prediction signal from the ILPM 426-1 and the D1 storedin the motion data module are fed to the M/TIAM 420-2 for performing theprocess of motion estimation. In the M/TIAM 420-2, the received D1 isadapted to have the output of the desired resolution. In oneimplementation, the received D1 is adapted to the resultant CIF output.

For producing the CIF output, the MB modes and the MVs are the primeattributes to be calculated. The MB modes refer to the degree ofpartition in the macroblocks. For example, mode 1 refers to an MB havingone partition of 16×16 pixels, mode 2 refers to an MB having twopartitions of 16×8 pixels, mode 3 refers to an MB having two partitionsof 8×16 pixels, and so on. Also, the macroblock can be coded using intermode or intra mode.

As part of the calculation, MB modes and MVs from D1 are adapted to theCIF output by using the principle of dominant mode. Since the overlaparea may not be an integral multiple of the number of MBs, the candidateMBs from D1 are selected based on width and height ratios and overlaparea. Further, based on the MB modes of the candidate MBs in D1, asingle MB mode is calculated for a corresponding MB in CIF. Thecandidate MBs are those MBs that qualify for being mapped based on widthand height ratios and the overlap area. A single MB mode can becalculated either by forward prediction or intra prediction. However, ifany of the candidate MB modes is intra mode, then the resultant singleMB mode is calculated as intra mode, irrespective of the dominant MBmode.

Also, each MB is checked by the encoder 316 if it can be skipped. The MBcan be skipped if the corresponding MV is zero or very close to zero.This situation can arise when the closet matching region is at the sameor almost at the same position in the reference frame and the energy ofa residual MB is low. The residual MB is formed by subtracting thereference MB (without motion compensation) from the current MB. Theenergy of the residual MB is approximated by SAD values. Therefore, ifthe cost of coding the MB as skip is lesser than that decided by theM/TIAM 420-2, then skip mode can be followed. This corresponds to theact of dealing away from the task of coding the current macroblock, andthus reducing computational load.

The MB mode corresponds to the degree of partitioning appearing in amacroblock, such as partitions of 16×16 or 16×8 or 8×16 or 8×8. The MBmode for the CIF MB is decided using the principle of dominant MB modepartition. Depending upon the dominant partition mode among thecandidate MBs of D1, the final CIF MB mode partition is decided.Further, an MV for the MB in the image of CIF resolution is decidedbased on MB mode partition and candidate MVs in D1 image. The candidateMVs are MVs corresponding to the candidate MBs. It is to be noted thatfour MBs of D1 are combined to form one MB of CIF image.

When the CIF MB mode is calculated as 16×16, the final MV of the CIF MBis calculated as the median of candidates in a set of four candidate MVsin D1. Further, if any of the candidate MB in D1 is not 16×16, the MV ofthe top left sub-partition is considered to be the MV of the completeMB.

When the CIF MB mode is calculated as 16×8, the MV for the top 16×8partition is calculated as the median of the MVs of top two 16×16 MBs inD1, while the MV of the bottom 16×8 partition is the median of the MVsof bottom two 16×16 MBs in D1. Further, if any of the candidate MBs inD1 is not 16×16, the MV of top left sub-partition is considered to bethe MV of the complete MB.

When the CIF MB mode is calculated as 8×16, the final MV of the left8×16 partition is calculated as the median of left two 16×16 MBs in D1,and the MV of the right 8×16 partition is the median of the right two16×16 MBs in D1. Further, if any of the candidate MBs in D1 is not16×16, the MV of the top left-partition is considered to be the MV ofthe complete MB.

When the CIF MB mode is calculated as 8×8, the MV for each 8×8 MBpartition at CIF resolution is equaled to MV of the corresponding 16×16MB in D1. The calculated motion information including MBs and MVs forthe CIF resolution and other related information thereto, are then sentto MRM 422-2 for further refinement of the CIF resolution.

MRM 422-2 receives the motion information from the M/TIAM 420-2 and theresized spatial data from the spatial down-converter module 314. In theMRM 422-2, the calculated MVs of the CIF resolution from M/TIAM 420-2undergo a refinement process based on the received resized spatial data.For the purpose, slight approximations are further added to the motioninformation, including the calculated MVs, for finding the best possiblemode for the MB located in the current frame. This is performed so thatMB located in the current picture is closest to the mode of the MBlocated in the reference frame. The approximations are found out byusing various techniques already known in the art. The process ofrefinement is carried out at the most granular level corresponding tothe refinement of motion information at quarter of a pixel (QPel) level.The refined motion data and spatial data (RMS) are then forwarded toTECM 426-2.

In TECM 426-2, in an implementation, RMS subsumed in each block of theconstructed macroblock, which forms the CIF resolution, is transformedinto low frequency DOT coefficient values using a variety oftransformation techniques already known in the art. The refined motiondata and spatial data are then entropy coded using a number of entropycoding techniques such as context-based adaptive variable-length coding(OAVLC), context-based adaptive binary arithmetic coding (CABAL), and soon. Therefore, a desired encoded CIF resolution output is received asthe output of TECM 426-2 that is sent to the multiplexer 318.

Enhancement Layer II

For obtaining an output that is having inherently the same resolution asthat of the original input signal, which forms a part of the finalscalable video signal, the enhancement layer II 432 is used. The spatialand motion information included in the original H.264/AVC coded videosignal is directly reused, thereby removing the requirement of M/TIAM.The input spatial data from the spatial data module 314 is fed directlyto the enhancement layer II 432 of the encoder 316 without resiting. Inan encoder with more than 3 layers, the top-most enhancement layer willbe configured in a manner similar to that of enhancement layer II 432,while the intermediate enhancement layers will be configured in a mannersimilar to that of enhancement layer I 430.

The enhancement layer II 432 includes ILPM 426-2, MRM 422-3, an TECM424-3. The ILPM 426-2 provides an exploitation of the statisticaldependencies between different layers for improving the codingefficiency of the enhancement layer. The improvement in codingefficiency can refer to a reduction in bit rate. The ILPM 426-2 usesvarious inter-layer prediction methods employing the reconstructedsamples from enhancement layer I 430 to produce an inter-layerprediction signal. The inter-layer prediction signal can be formed byusing different methods such as motion compensated prediction inside theenhancement layer, by up-sampling the reconstructed enhancement layer I430 signal, and so on. These methods are dependent on variousparameters, for example, prediction of MB modes and associated motionvectors. Correspondingly, the encoder 316 checks for each MB at CIFresolution for it can be inter-layer predicted from the enhancementlayer I 430. Therefore, the encoder checks for intra, motion, andresidual inter-layer predictions while coding each MB. The inter-layerprediction signal from the ILPM 426-2 and the original spatialinformation stored in the spatial data module 314 are fed directly tothe MRM 422-3.

The MB information, such as MB mode, MB partition, and MVs, included inthe motion information are directly replicated as the input signal.Also, each MB is checked by the encoder 316 if it can be skipped. The MBcan be skipped if the corresponding MV is zero or very close to zero.This situation can arise when the closet matching region is at the sameor almost at the same position in the reference frame and the energy ofa residual MB is low. The energy of the residual MB formed bysubtracting the reference MB (without motion compensation) from thecurrent MB is approximated by SAD values. Therefore, if the cost ofcoding the MB as skip is less, then skip mode can be followed. Thiscorresponds to the act of dealing away from the task of coding thecurrent macroblock and reduces the computational load.

In MRM 422-3, only MVs are refined based on the received spatial data.For the purpose, slight approximations are further added to the motioninformation, which includes the calculated MVs, for finding the bestpossible mode for the MB located in the current frame. This is performedso that an MB located in the current frame is closest to the mode of theMB located in the reference frame. The approximations are found out byusing various techniques already known in the art. The process ofrefinement is carried out at the most granular level corresponding tothe refinement of motion information at quarter of a pixel (QPel) level.The refined motion data and spatial data (RMS) are then forwarded toTECM 424-3.

In TECM 424-3, in an implementation, RMS subsumed in each block of theconstructed macroblock, which is of the resolution equivalent to theoriginal resolution, is transformed into low frequency DOT coefficientvalues using a variety of transformation techniques already known in theart. RMS is then entropy coded using a number of entropy codingtechniques such as context-based adaptive variable-length coding(CAVLC), context-based adaptive binary arithmetic coding (CABAC), and soon. Therefore, the output of resolution equivalent to the originalresolution is received as the output of TECM 424-3, which is then sentto the multiplexer 318.

In the multiplexer 318, the SVC outputs of distinct resolutions fromeach layer, namely base layer 428, enhancement layer I 430, andenhancement layer II 432 are multiplexed. The multiplexing of SVCoutputs from different layers refers to the act of combing the receivedmultiple SVC outputs into a single signal. This single signal is thescalable output video signal 404 having multiple signals of differentresolutions. Also, the multiplexer 318 can be of differentconfigurations depending upon the number of signals to be multiplexed.

FIG. 5 illustrates an exemplary method 500 for implementing a NSV2SVconverter 110. These exemplary methods may be described in the generalcontext of computer executable instructions. Generally, computerexecutable instructions can include routines, programs, objects,components, data structures, procedures, modules, functions, and thelike that perform particular functions or implement particular abstractdata types. The computer executable instructions can be stored on acomputer readable medium and can be loaded or embedded in an appropriatedevice for execution.

The order in which the method is described is not intended to beconstrued as a limitation, and any number of the described method blockscan be combined in any order to implement the method, or an alternatemethod. Additionally, individual blocks may be deleted from the methodwithout departing from the spirit and scope of the subject matterdescribed herein. Furthermore, the method can be implemented in anysuitable hardware, software, firmware, or combination thereof.

At block 502, an input signal is received and decoded. In oneimplementation, the input signal can be a non-scalable video signal 402subsuming a single layer bit stream of a certain resolution. Forexample, the non-scalable video signal 402 can be a video signal codedin any video coding standard such as H.264/AVC, MPEG-2, and so on thatsupports scalability. The non-scalable video signal 402 is received bythe NS2SV converter 110 from the broadcasting station servers 104 viathe network 106. The received video signal is then decoded by thedecoder 306.

In one implementation, the decoder 306 converts the received videosignal into a signal that can be adapted in any intermediate format suchas Common Intermediate Format (CIF), Quarter Common Intermediate Format(QCIF), and so on. The received video signal undergoes variable-lengthdecoding (VLD) 408 using techniques known in the art. The decoded signalis subjected to inverse quantization 410 determining the class andquantization number of the quantized discrete cosine transform (DOT)coefficient values included in the decoded signal.

Further, the quantized DOT coefficient values are reciprocated at theinverse DCT (IDCT) 412 to produce the IDCT coefficient values. Theoutput of the IDCT is added with output of the motion compensation stage414 to produce a smooth video sequence. The motion compensation can beperformed by a variety of techniques such as block motion compensation,overlapped motion compensation, variable block-size motion compensationand so on.

At block 504, a decoded signal is subjected to the segmentation section406. In one implementation, the processors 302 segment the decodedsignal using segmentation techniques well known in the art. The decodedsignal is segmented into the spatial data, which is stored in spatialdata module 310 and the motion data, which is stored in motion datamodule 312. The spatial data module 310 and the motion data module 312can be stored in the system memory 308. The spatial data module 310stores the decoded spatial data as pixel data information. The pixeldata can be associated with attributes such as, for example, picturedata, picture width, picture height, and so on, in a picture frame ofthe video sequence. The motion data describes the location of differentcomponents in a picture frame such as pixels, blocks, macroblocks (MBs)and so on, and other related attributes such as MB modes, MB motion typeand so on.

At block 506, spatial data is sampled to a desired resolution. In oneimplementation, the spatial data is down sampled by a spatialdown-converter module 310 to adjust the corresponding data size. Thedown sampling of the spatial data enables resizing of the spatial datato conform to the desired resolution depending upon the targeted enddevices 112. The down sampling of the spatial data reduces the data rateor the size of the data. The reduction in size of the spatial data isachieved based on the desired resolution such as Common IntermediateFormat (CIF) resolution, Quarter CIF (QCIF) resolution, and so on. Thedown-sampling operation can be performed using a variety of techniqueswell known in the art. For example, the spatial data can be sampled byusing various image compression filters such as polyphase filters,wavelet filters, and so on.

At block 508, the sampled spatial data and original motion data issubmitted to an encoder, such as the encoder 316. In one implementation,the down-sampled spatial data and the original motion data is submittedto different layers of the encoder 316. The original motion data isobtained from the VLD 408 and fed to the encoder 316. The encoder 316includes a multitude of layers each having a distinct resolution. In oneimplementation, the encoder can include a base layer 428, an enhancementlayer I 430, an enhancement layer II 432. For example, the base layer428 has 640×480 resolutions, whereas the enhancement layer I 430 has1280>720 resolutions, and so on. The base layer 428 includes M/TIAM420-1, MRM 422-1 and TECM 424-1, the enhancement layer 1428 includesM/TIAM 420-2, MRM 422-2, TECM 424-2 and ILPM 426-1, and the enhancementlayer II 432 includes MRM 422-3, TECM 424-3 and ILPM 428-2.

At block 510, motion data is adapted to a desired resolution. In oneimplementation, the motion data received from the segmentation section406 is adapted to the desired resolution of each layer, except thetop-most enhancement layer. The motion data is fed into theMotion/Texture Info Adaptation Module (M/TIAM) 420 of each layer forcalculating the motion information such as motion vector (MV) for theresultant decoded signal. The motion information calculated in theprevious layer can be used by the next layer. For example, the motioninformation calculated by the M/TIAM 420-1 of the base layer 428 can beused by the ILPM 426-1 of the enhancement layer I 430. Further, themotion information calculated by the M/TIAM 420-2 of the enhancementlayer I 430 can be used by the ILPM 426-2 of the enhancement layer II432, and so on. However, the M/TIAM 420 is not present for the top-mostenhancement layer since the information from the input is being directlyreused. The top-most enhancement layer is adapted at the same resolutionof the input signal.

At block 512, the encoder performs Inter-Layer Prediction for thecurrent layer from the layer of lower resolution to provide furthercompression. At block 514, the adapted motion data are refined based onthe down sampled spatial data. In one implementation, the calculatedmotion information from the M/TIAM 420 undergoes a refinement process atthe Motion Refinement Module (MRM) 422 based on the down sampled spatialdata to improve the quality of the resulting motion information. The MRM422 performs slight approximations on the calculated motion informationincluding the calculated MVs in all the layers for finding the bestpossible mode for the MB located in the current picture frame. Theapproximations can be performed by using various techniques alreadyknown in the art.

At block 516, the refined motion data and spatial data are transformedinto discrete cosine transform (DCT) coefficient values. In oneimplementation, the refined motion information and the spatial dataundergo transformation, for example, discrete cosine transformation. Thetransformation results in discrete cosine transform (DCT) coefficientvalues of the refined motion data and spatial data.

At block 518, the DOT coefficient values are entropy-encoded. In oneimplementation, in each layer, the DOT coefficient values obtained inthe block 514 are compressed using compression techniques known in theart. In one implementation, an entropy-encoding technique is applied onthe DCT coefficient values and an encoded video signal is obtained.

At block 520, the transformed and entropy-encoded data is multiplexed.In one implementation, the transformed and encoded data obtained in eachlayer are provided as input to the multiplexer 318. The multiplexer 318combines the transformed and encoded data from each layer into a singledata corresponding to a single video signal.

At block 522, a scalable output video signal is produced. In oneimplementation, the output of the multiplexer 318 can be a single videosignal that exhibits a scalable video signal 404. The scalable videosignal 404 can be a multi-layer bit stream subsuming a distinctresolution in each layer. The scalable video signal 404 is encoded inthe SVC standard.

Although embodiments for a NSV2SV converter have been described inlanguage specific to structural features and/or methods, it is to beunderstood that the appended claims are not necessarily limited to thespecific features or methods described. Rather, the specific featuresand methods are disclosed as exemplary implementations for theprogrammable compensation network.

1. A system comprising: an intermediate device; a communicationsnetwork; a broadcasting system configured to transmit a non-scalableinput video signal to said intermediate device via said communicationsnetwork; said intermediate device comprising a converter configured toconvert the non-scalable input video signal into a scalable output videosignal having a multi-layer bit stream, each layer corresponding to adifferent resolution, said converter being configured to reuse motioninformation from the non-scalable input video signal to generate thescalable output video signal; and a receiving device configured toreceive the scalable output video signal from said intermediate deviceand use layers from the multi-layer bit stream corresponding to asupported resolution.
 2. The system as claimed in claim 1, wherein saidbroadcasting system comprises one of a satellite, and a satellite alongwith a plurality of broadcasting station servers cooperating therewith.3. The system as claimed in claim 1, wherein the receiving devicecomprises one of a mobile communication device, a telecommunicationdevice, and a computing device.
 4. The system as claimed in claim 1,wherein at least one of said receiving device and said intermediatedevice comprises an extractor configured to extract layers from themulti-layer bit stream corresponding to the resolution supported by thereceiving device.
 5. A system comprising: a broadcasting system fortransmitting a non-scalable input video signal; said broadcasting systemcomprising a converter configured to convert a non-scalable input videosignal into a scalable output video signal having a multi-layer bitstream, each layer corresponding to a different resolution, saidconverter being configured to reuse motion information from thenon-scalable input video signal; a communications network; and areceiving device configured to receive the scalable output video signalfrom said converter via said communications network, said receivingdevice being configured to render layers from the multi-layer bit streamcorresponding to a resolution supported thereby.
 6. The system asclaimed in claim 5, wherein said receiving device comprises an extractorconfigured to extract layers from the multi-layer bit stream.
 7. Thesystem as claimed in claim 5, wherein said receiving device is one of amobile communication device, a telecommunication device, and a computingdevice.
 8. A device for converting a non-scalable input video signaltransmitted via a communications network from a broadcasting system to ascalable output video signal for a downstream receiving device, thedevice comprising: a decoder configured to receive, via saidcommunications network, and decode the non-scalable input video signalto produce a decoded signal; and an encoder configured to reuse spatialdata and motion data in the decoded signal to generate a plurality ofencoded signals for the downstream receiving device, the encoder beingconfigured to multiplex the plurality of encoded signals to generate thescalable output video signal.
 9. The device as claimed in claim 8,wherein the non-scalable input video signal comprises a single layer bitstream.
 10. The device as claimed in claim 8, wherein the non-scalableinput video signal comprises a non-scalable input video signal coded asper H.264/AVC standard.
 11. The device as claimed in claim 8, whereinthe scalable output video signal comprises a scalable output videosignal coded as per Scalable Video Coding (SVC) standard.
 12. The deviceas claimed in claim 8 further comprising a motion data module configuredto store the motion data.
 13. The device as claimed in claim 8 furthercomprising a spatial data module configured to store the spatial data.14. The device as claimed in claim 8 further comprising a spatialdown-converter module configured to down-sample the spatial data. 15.The device as claimed in claim 8, wherein said encoder comprises aplurality of encoding layers each corresponding to a differentresolution.
 16. The device as claimed in claim 15, wherein the encodinglayers comprise at least one of an adaptation module, an inter-layerprediction module, a motion refinement module, and a transform andentropy encoding module.
 17. The device as claimed in claim 16, whereinthe adaptation module is configured to adapt the motion data to conformto the different resolution of the corresponding layer; wherein saidmotion refinement module being configured to refine at least one of themotion data, the adapted motion data, and the spatial data to generaterefined motion and spatial data; wherein said inter-layer predictionmodule being configured to predict motion information based on theadapted motion data of a previous encoding layer; and wherein saidtransform and entropy encoding module being configured to transform andentropy encode the refined motion and spatial data to produce an encodedsignal.
 18. A method for converting a non-scalable input video signal toa scalable output video signal, the method comprising: receiving thenon-scalable input video signal from a broadcasting system via acommunications network; decoding the non-scalable input video signal toproduce a decoded signal using a decoder; generating a plurality ofencoded signals by reusing motion information included in the decodedsignal, the plurality of encoded signals corresponding to differentresolutions using an encoder; and multiplexing, also using the encoder,the plurality of encoded signals to generate the scalable output videosignal for a downstream receiving device.
 19. The method as claimed inclaim 18, wherein the non-scalable input video signal comprises a singlelayer bit stream.
 20. The method as claimed in claim 18, wherein thenon-scalable input video signal comprises a non-scalable input videosignal coded as per H.264/AVC standard.
 21. The method as claimed inclaim 18, wherein the scalable output video signal comprises a scalableoutput video signal coded as per Scalable Video Coding (SVC) standard.22. The method as claimed in claim 18, wherein generating the pluralityof encoded signals comprises: segmenting the decoded signal byextracting spatial data and motion data for reuse; down-sampling theextracted spatial data to multiple resolutions; and transmitting thedown-sampled spatial data to multiple encoding layers, each encodinglayer corresponding to a resolution from the multiple resolutions of thedown-sampled spatial data.
 23. The method as claimed in claim 22 furthercomprising, at each encoding layer: adapting the motion data to thecorresponding resolution; refining the adapted motion data and thedown-sampled spatial data to produce refined motion and spatial data;and transforming and encoding the refined motion and spatial data toproduce an encoded signal.
 24. A non-transitory computer-readable mediumcomprising computer executable instructions for converting anon-scalable input video signal to a scalable output video signal, thecomputer-readable medium comprising instructions for: receiving thenon-scalable input video signal from a broadcasting system via acommunications network; decoding the non-scalable input video signal toproduce a decoded signal; generating a plurality of encoded signals byreusing motion information included in the decoded signal, the pluralityof encoded signals corresponding to different resolutions; andmultiplexing the plurality of encoded signals to generate the scalableoutput video signal for a downstream receiving device.
 25. Thenon-transitory computer-readable medium as claimed in claim 24, whereingenerating the plurality of encoded signals comprises: segmenting thedecoded signal by extracting spatial data and motion data for reuse;down-sampling the extracted spatial data to multiple resolutions; andtransmitting the down-sampled spatial data to multiple encoding layers,each encoding layer corresponding to a resolution from the multipleresolutions of the down-sampled spatial data.
 26. The non-transitorycomputer-readable medium as claimed in claim 25, further comprisinginstructions for, at each encoding layer: adapting the motion data tothe corresponding resolution; and refining the adapted motion data andthe down-sampled spatial data to produce refined motion and spatialdata; and transforming and encoding the refined motion and spatial datato produce an encoded signal.